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Background Infertility, an important source of stress, could affect sexual life. Extensive studies suggest that the incidence of sexual dysfunction is highly prevalent in infertile women. As the duration of infertility increases, the level of stress is also likely to increase even further, and this could aggravate psychological pain and cause sexual dysfunction. However, the effect of infertility duration on sexual health is unclear. Methods We conducted a case-control study in which 715 patients participated between September 1,2020 and December 25, 2020. We included patients diagnosed with infertility (aged between 20 to 45), who were divided into four groups according to their infertility durations: ≤ 2 years (Group I, n = 262), > 2 years but ≤ 5 years (Group II, n = 282), > 5 years but ≤ 8 years (Group III, n = 97), and > 8 years (Group IV, n = 74). A questionnaire survey on female sexual functions and psychological depression was administered to participants, and their female sexual functions and depression status were measured using the Female Sexual Function Index (FSFI) and Patient Health Questionnaire (PHQ-9), respectively. Results As the number of years of infertility increased, the PHQ-9 score as well as the incidence of psychological depression increased significantly (p < 0.05), but the total score of FSFI and those of its six domains/sub-scales were not significantly different among the four groups. An analysis of the relevant factors affecting sexual functions, using the multivariable logistic regression model, revealed that when the infertility duration was greater than 8 years, there was a significant increase in the incidence of sexual dysfunction [adjusted odds ratios (AOR) = 5.158, 95% confidence interval (CI): 1.935–13.746, P = 0.001], arousal disorder (AOR = 2.955, 95% CI: 1.194–7.314, P = 0.019), coital pain (AOR = 3.811, 95% CI: 1.045–13.897, P = 0.043), and lubrication disorder (AOR = 5.077, 95% CI: 1.340–19.244, P = 0.017). Conclusions An increasing infertility duration is a risk factor for the occurrence of sexual dysfunction. Hence, as the infertility duration increases, the incidence of female sexual dysfunction and psychological distress could also increase, especially when the infertility duration is more than 8 years.

Extranodal natural killer/T‐cell lymphoma, nasal type (ENKL) is a rare peripheral T‐cell lymphoma that predominantly occurs in Asian and South American populations. The treatment of ENKL has been a challenge for a long time. This study was conducted to compare the clinical efficacy and safety of cisplatin, dexamethasone, gemcitabine, and pegaspargase (DDGP) and methotrexate, dexamethasone, ifosfamide, L‐asparaginase, and etoposide (SMILE) regimens for relapsed/refractory ENKL and explore the prognostic factors. From October 2014 to July 2019, 54 patients with relapsed/refractory ENKL who received DDGP or SMILE chemotherapy were retrospectively assessed in this study. Thirty‐one patients received DDGP chemotherapy and 23 patients received SMILE chemotherapy. A higher complete response rate was observed in patients treated with DDGP regimen (61.3% vs. 30.4%, P = 0.025). The DDGP group (95% confidence interval (CI) of 5‐year progression‐free survival (PFS): 24.6–66.2%; 95% CI of 5‐year overall survival (OS): 8.5–91.7%) was also significantly associated with longer 5‐year PFS and 5‐year OS (P = 0.008 for 5‐year PFS, P = 0.023 for 5‐year OS). More serious leucopenia (P = 0.021), neutropenia (P = 0.041), and allergy (P = 0.040) were observed in the SMILE group. Post‐treatment Epstein–Barr virus (EBV)‐DNA status (P = 0.001 for PFS, P = 0.018 for OS) was identified as a significant prognostic factor for PFS and OS in multivariate analysis. The present research suggested that compared with SMILE chemotherapy, DDGP chemotherapy can significantly improve the response and survival of relapsed/refractory ENKL with better tolerance. Post‐treatment EBV‐DNA status was identified as a significant prognostic factor for PFS and OS in relapsed/refractory ENKL.

Several studies have indicated that stroke survivors with multiple lesions or with larger lesion volumes have a higher risk of stroke recurrence. However, the relationship between lesion locations and stroke recurrence is unclear. We conducted a prospective cohort study of first-ever ischemic stroke survivors who were consecutively enrolled from January 2010 to December 2015. Stroke recurrence was assessed every 3 months after post-discharge via telephone interviews by trained interviewers. Lesion locations were obtained from hospital-based MRI or CT scans and classified using two classification systems that were based on cerebral hemisphere or vascular territory and brain anatomical structures. Flexible parametric survival models using the proportional hazards scale (PH model) were used to analyze the time-to-event data. Among 633 survivors, 63.51% (n=402) had anterior circulation ischemia (ACI), and more than half of all ACIs occurred in the subcortex. After a median follow-up of 2.5 years, 117 (18.48%) survivors developed a recurrent stroke. The results of the multivariate PH model showed that survivors with non-brain lesions were at higher risk of recurrence than those with right-side lesions (HR, 2.79; 95%CI, 1.53, 5.08; P=0.001). There was no increase in risk among survivors with left-side lesions (HR, 0.97; 95%CI, 0.53, 1.75; P=0.914) or both-side lesions (HR, 1.24; 95%CI, 0.75, 2.07; P=0.401) compared to those with right-side lesions. Additionally, there were no associations between stroke recurrence and lesion locations that were classified based on vascular territory and brain anatomical structures. It was concluded that first-ever ischemic stroke survivors with non-brain lesion had higher recurrence risk than those with right-side lesion, although no significant associations were found when the lesion locations were classified by vascular territory and brain anatomical structures.

Compared with conventional image sensors, event cameras have been attracting attention thanks to their potential in environments under fast motion and high dynamic range (HDR). To tackle the lost-track issue due to fast illumination changes under HDR scene such as tunnels, an object tracking framework has been presented based on event count images from an event camera. The framework contains an offline-trained detector and an online-trained tracker which complement each other: The detector benefits from pre-labelled data during training, but may have false or missing detections; the tracker provides persistent results for each initialised object but may suffer from drifting issues or even failures. Besides, process and measurement equations have been modelled, and a Kalman fusion scheme has been proposed to incorporate measurements from the detector and the tracker. Self-initialisation and track maintenance in the fusion scheme ensure autonomous real-time tracking without user intervene. With self-collected event data in urban driving scenarios, experiments have been conducted to show the performance of the proposed framework and the fusion scheme.

In this paper, we propose a novel surface plasmon resonance sensor for both liquid and gas detections, which is based on the two dielectric planar waveguide (PWG)-coupled plasmonic structure. Two sharp Fano-type resonances, which arise from the electromagnetic coupling between surface plasmon polariton (SPP) and PWG modes, appear in the reflection curve, and they can be used to monitor the minute changes of the refractive indices of gas and liquid due to their high imaging sensitivities (> 9.0 × 103 RIU− 1). The Fano resonance angles and the figures of merit for imaging sensitivity can be effectively manipulated by the thicknesses of guiding layers, and the sensor system can measure over a wide range of the refractive indices of sensing media.

In this work, we theoretically propose a highly-flexible optical bistable switch based on a suspended monolayer Z-shaped graphene nanoribbon nanoresonator (NR). It is shown that bistable nonlinear absorption and refraction response will appear in the strong exciton-NR coupling rme. Specifically, we plot bistability phase diagrams within the system’s parameter subspace and derive the critical conditions for optical bistability (OB), which allow one to switch precisely and efficiently OB on/off. The scheme proposed here not only provides a unique platform for measuring the coupling strength between the exciton and the NR, but also may eventually enable applications in the quantum optics and quantum information processing.

A miniature reflectron time-of-flight mass spectrometer (TOF MS) with orthogonal extraction coupled with electron impact (EI) ionization source can be used to perform in situ gas composition analysis in a planetary environment. However, performances such as the mass resolution, sensitivity, limit of detection, mass range, and mass accuracy are often decreased because of miniaturization. Herein, a compact instrument for space applications has been developed, and its performance has been evaluated. The mass of the TOF MS is 13.4 kg, with dimensions of 300 mm × 200 mm × 200 mm, and the power consumption is 25 W. In this paper, the design of the ion source, mass analyzer, and detector is discussed in detail. The upper limit of the mass range is greater than 500 amu, and the best resolving power obtained so far on the miniature TOF MS is around 405 at full width half maximum (FWHM); other performance indexes of the instrument are also determined, where the worst case for mass stability is 0.49%, together with a mass accuracy of 0.12% and a sensitivity of 0.6 mV/ppm.

Spiking neural networks (SNNs) possess energy-efficient potential due to event-based computation. However, supervised training of SNNs remains a challenge as spike activities are non-differentiable. Previous SNNs training methods can be generally categorized into two basic classes, i.e., backpropagation-like training methods and plasticity-based learning methods. The former methods are dependent on energy-inefficient real-valued computation and non-local transmission, as also required in artificial neural networks (ANNs), whereas the latter are either considered to be biologically implausible or exhibit poor performance. Hence, biologically plausible (bio-plausible) high-performance supervised learning (SL) methods for SNNs remain deficient. In this paper, we proposed a novel bio-plausible SNN model for SL based on the symmetric spike-timing dependent plasticity (sym-STDP) rule found in neuroscience. By combining the sym-STDP rule with bio-plausible synaptic scaling and intrinsic plasticity of the dynamic threshold, our SNN model implemented SL well and achieved good performance in the benchmark recognition task (MNIST dataset). To reveal the underlying mechanism of our SL model, we visualized both layer-based activities and synaptic weights using the t-distributed stochastic neighbor embedding (t-SNE) method after training and found that they were well clustered, thereby demonstrating excellent classification ability. Furthermore, to verify the robustness of our model, we trained it on another more realistic dataset (Fashion-MNIST), which also showed good performance. As the learning rules were bio-plausible and based purely on local spike events, our model could be easily applied to neuromorphic hardware for online training and may be helpful for understanding SL information processing at the synaptic level in biological neural systems., Comment: 29 pages, 6 figures

To assess the associations between air pollution and the pregnancy rate of IVF, we performed a retrospective cohort study on 1455 women who underwent the first fresh IVF cycle at a fertility center from January 2014 to April 2018 and lived in Shenyang during treatment. Binary logistic regression models were used to evaluate the effect of an interquartile range increase in each pollutant on the intrauterine pregnancy rate. Both average chronic and daily acute exposure to air pollution were considered. Increased O3 (adjusted OR = 0.87, 95% CI: 0.81, 0.98) during the period from gonadotropins starting to oocyte retrieval was associated with decreased probability of intrauterine pregnancy, especially the day before oocyte retrieval (adjusted OR = 0.86, 95% CI: 0.78, 0.95). Our results suggest that exposure to O3 before oocyte retrieval has an adverse effect on intrauterine pregnancy. Future studies should be performed in order to confirm our findings.

Polycystic ovary syndrome (PCOS) is a common endocrine disease accompanied by energetic metabolic imbalance. Because the etiology of PCOS is complex and remains unclear, there is no effective and specific treatment for PCOS. It is often accompanied by various metabolic disorders such as obesity, insulin resistances, and others. Activated brown adipose tissue (BAT) consumes excess energy via thermogenesis, which has positive effects on energy metabolism. Our previous research and that of others indicates that BAT activity is decreased in PCOS patients, and exogenous BAT transplantation can improve PCOS rodents. Notably however, it is difficult to apply this therapeutic strategy in clinical practice. Therapeutic strategies of enhancing endogenous BAT activity and restoring whole-body endocrine homeostasis may be more meaningful for PCOS treatment. In the current study, the dehydroepiandrosterone-induced PCOS rat was exposed to low temperature for 20 days. The results show that cold treatment could reverse acyclicity of the estrous cycle and reduce circulating testosterone and luteinizing hormone in PCOS rats by activating endogenous BAT. It also significantly reduced the expression of steroidogenic enzymes as well as inflammatory factors in the ovaries of PCOS rats. Histological investigations revealed that cold treatment could significantly reduce ovary cystic follicles and increase corpus luteum, indicating that ovulation was recovered to a normal level. Concordant with these results, cold treatment also improved fertility in PCOS rats. Collectively, these findings suggest that cold treatment could be a novel therapeutic strategy for PCOS.

Objective: This study aimed to evaluate the safety, efficacy, and feasibility of the rituximab, fotemustine, pemetrexed, and dexamethasone (R-FPD) regimen followed by whole-brain radiotherapy (WBRT) for patients with primary central nervous system lymphoma (PCNSL). Methods: A prospective, single-center phase II clinical trial was conducted. Patients with PCNSL newly diagnosed at the First Affiliated Hospital of Zhengzhou University between July 2018 and July 2020 were studied. The R-FPD regimen consisted of rituximab (375 mg/m2 i.v. on D0), fotemustine (100 mg/m2 i.v. on D1), pemetrexed (600 mg/m2 i.v. on D1), and dexamethasone (40 mg i.v. on D1-5). Patients 60 years or younger who showed a complete response (CR) were treated with 23.4 Gy of WBRT after the end of chemotherapy; those older than 60 years with CR were treated with a wait-and-see approach; and those who did not show CR after the 4th cycle of chemotherapy were given salvage WBRT 30 Gy + local tumor field irradiation up to 45 Gy, regardless of age. Results: A total of 30 patients were included. After 2 cycles, the objective response rate (ORR) was 96.5% (28/29, 1 CR, 27 PR, 0 SD, and 1 PD). After 4 cycles, the ORR was 73.1% (19/26, 11 CR, 8 PR, 4 SD, and 3 PD). After WBRT, the ORR was 90.9% (10/11, 7 CR, 3 PR, and 1 SD). The grade III and IV toxicity responses were mainly leukopenia (20.0%), thrombocytopenia (23.3%), and anemia (10.0%). Conclusions: Fotemustine-based therapy in combination with rituximab chemotherapy followed by WBRT can improve outcomes, providing ORR benefits and favorable tolerability in patients newly diagnosed with PCNSL.

Background To date, there have been no reports on the sexual and psychological health of patients with azoospermia during the coronavirus disease 2019 (COVID-19) pandemic. Previous studies on the sexual health of couples with azoospermia are limited and are especially lacking in data on the wives of azoospermic men. Methods We conducted a case–control cross-sectional study between 1 July 2020 and 20 December 2020. In total, 100 couples with azoospermia comprised the experimental group and 100 couples with normozoospermia comprised the control group. The couples’ sexual health was measured using standardised sexual function questionnaires (male: International Index of Erectile Function-15 [IIEF-15] and Premature Ejaculation Diagnostic Tool [PEDT]; female: Female Sexual Function Index [FSFI]) and a self-designed questionnaire to evaluate changes in sexual behaviours (sexual satisfaction, desire, frequency of sexual activity, masturbation, and pornography use) during lockdown. The couples’ psychological health was measured using the 7-item Generalized Anxiety Disorder (GAD-7) scale and 9-item Patient Health Questionnaire (PHQ-9). The Actor–Partner Interdependence Model (APIM) was used to analyse the associations between sexual health and psychological health. Results The IIEF-15 scores (53.07 ± 11.11 vs. 57.52 ± 8.57, t = − 3.17, p = 0.00) were lower and the PEDT scores (6.58 ± 3.13 vs. 5.17 ± 2.22, t = 3.67, p = 0.00) and incidence of premature ejaculation (χ2 = 14.73, p = 0.00) were higher for men with azoospermia than for men with normozoospermia. Compared with those of wives of men with normozoospermia, the total FSFI scores (25.12 ± 5.56 vs. 26.75 ± 4.82, t = − 2.22, p = 0.03) of wives of men with azoospermia were lower. The chi-square test showed that the perceived changes in sexual satisfaction (χ2 = 7.22, p = 0.03), frequency of masturbation (χ2 = 21.96, p = 0.00), and pornography use (χ2 = 10.90, p = 0.01) were significantly different between the female groups with azoospermia and normozoospermia, but there were no significant changes in sexual behaviour between the male groups. The GAD-7 (men: 7.18 ± 5.56 vs. 5.68 ± 4.58, p = 0.04; women: 6.65 ± 5.06 vs. 5.10 ± 3.29, p = 0.01) and PHQ-9 scores (men: 10.21 ± 6.37 vs. 7.49 ± 6.10, p = 0.00; women: 8.81 ± 6.50 vs. 6.98 ± 4.43, p = 0.02) were significantly higher for couples with azoospermia than for couples with normozoospermia. The APIM showed that for couples with azoospermia, sexual function negatively correlated with their own anxiety (men: β = −0.22, p = 0.00; women: β = −0.38, p = 0.00) and depression symptoms (men: β = −0.21, p = 0.00; women: β = −0.57, p = 0.00) but not with their partner’s anxiety and depression symptoms (p > 0.05). Conclusions Couples with azoospermia had a lower quality of sexual function and higher levels of psychological distress than couples with normozoospermia. Their sexual health negatively correlated with psychological distress.

Type 2 diabetes is currently experiencing an outbreak worldwide. GLP-1 effectively lowers blood glucose level as an emerging target for the treatment of type 2 diabetes. However, the application of GLP-1 is limited by short half-life and too expensive cost in clinic. In this study we employed the food-grade probiotics as delivery system to express human GLP-1 and its analogue. Recombinant lactococcus lactis could express GLP-1 and analogue in vitro and modified GLP-1 analogue was more resistant to DPP-4 degradation. Oral administration of GLP-1 analogue could reduce the fat mass. More importantly, GLP-1 analogue improved hyperglycemia and insulin resistance in Db/Db mouse although the insulin secretion is not observed in vitro. Our study demonstrates that lactococcus lactis genetically modified with single amino acid mutation could prolong half-life of GLP-1 and increase insulin sensitivity in Db/Db mouse model as an oral drug delivery system driving the development and innovation of drug therapy for type 2 diabetes.

Obeticholic acid (OCA) is exemplified as a potent drug for treating primary biliary cirrhosis and nonalcoholic fatty liver disease by inhibiting bile acid synthesis. However, it remains unclear whether the effect of OCA is mediated by the function of brown adipose tissue (BAT). In the present study, brown adipogenesis differentiation in vitro and db/db mouse model treated with OCA were used to assess the anti-obesity function by body weight tracking, O2 consumption, food intake, physical activity, glucose tolerance tests. In addition, uncoupling protein 1 (Ucp1) protein expression in brown adipose tissue was measured by western blotting, morphometry of brown adipose tissue was analyzed by hematoxylin and eosin staining. Hepatic steatosis was detected by Oil-Red O staining and serological analysis was performed to assess the effect of OCA on hyperlipidemia. OCA treatment enhanced brown adipocyte cell differentiation and upregulated the expression of the BAT-specific gene Ucp1) in C3H10T1/2 cells in vitro. Consistent with these findings, OCA increased whole-body energy metabolism and glucose homeostasis by enhancing BAT activity in vivo, and ultimately decreased body weight gain in db/db mice. In addition, the results demonstrated that spontaneous hepatic steatosis in db/db mice was ameliorated following OCA treatment. In summary, OCA functioned as a BAT activator to help ameliorate obesity and maintain glucose homeostasis in db/db mice. The present results may provide a novel potential therapeutic approach to activate brown fat in patients with obesity and other metabolic disorders.

ObjectiveThe prognosis for patients with relapsed or refractory diffuse large B-cell lymphoma (R/R-DLBCL) after second-line treatment failure is extremely poor. This study prospectively observed the efficacy and safety of decitabine with a modified cisplatin, cytarabine, and dexamethasone (DHAP) regimen in R/R-DLBCL patients who failed second-line treatment.MethodsTwenty-one R/R-DLBCL patients were enrolled and treated with decitabine and a modified DHAP regimen. The primary endpoints were overall response rate (ORR) and safety. The secondary endpoints were progression-free survival (PFS) and overall survival (OS).ResultsORR reached 50% (complete response rate, 35%), five patients (25%) had stable disease (SD) with disease control rate (DCR) of 75%. Subgroup analysis revealed patients over fifty years old had a higher complete response rate compared to younger patients (P = 0.005), and relapsed patients had a better complete response rate than refractory patients (P = 0.031). Median PFS was 7 months (95% confidence interval, 5.1-8.9 months). Median OS was not achieved. One-year OS was 59.0% (95% CI, 35.5%-82.5%), and two-year OS was 51.6% (95% confidence interval, 26.9%-76.3%). The main adverse events (AEs) were grade 3/4 hematologic toxicities such as neutropenia (90%), anemia (50%), and thrombocytopenia (70%). Other main non-hematologic AEs were grade 1/2 nausea/vomiting (40%) and infection (50%). No renal toxicity or treatment-related death occurred.ConclusionDecitabine with a modified DHAP regimen can improve the treatment response and prognosis of R/R-DLBCL patients with good tolerance to AEs, suggesting this regimen has potential as a possible new treatment option for R/R-DLBCL patients after second-line treatment failure.Clinical Trial RegistrationClinicalTrials.gov, identifier: NCT03579082.

A high-performance HIMAC (HINOC Media Access Control layer) acceleration coprocessor for High-Performance Network over Coax (HINOC3.0) is presented in this paper. The design aims to provide wire-speed processing of up to 10G Ethernet frames. The design also completes the following functions: 1) Supports 2 to 16 channel bonding of the physical layer HIPHY (HINOC Physical layer); 2) Supports up to 128 terminal devices; 3) Supports the filtering and classification of Ethernet frames, completing operations such as assigning priority, discarding, and redirecting; 4) Supports mutual conversion between EMAC frame and HIMAC frame, by completing the encapsulating and splitting work; 5) Supports data exchange between EMAC interface and HIMAC interface. With the implementation of FPGAs, this HIMAC design can support wire-speed processing of up to 10G Ethernet frames and provide media access control layer functions for HINOC3.0.

Efficiently retrieving synthetic aperture radar (SAR) image is an important yet challenging task in the remote sensing field. Due to the shortage of labeled SAR images for fine-tuning convolutional neural network (CNN) models, this letter presents an unsupervised domain adaptation model based on CNN to learn the domain-invariant feature between SAR images and optical aerial images for SAR image retrieving, which can alleviate the burden of manual labeling. We extend a deep CNN to a novel adversarial network by adding the domain discriminator and the pseudolabel predictor. We improve the adaptation capacity of the adversarial network by utilizing the class information of SAR training images, which is obtained by clustering. Compared with the other related methods, the proposed method can enhance retrieval performance with our SAR data set.

INTRODUCTION Although experimental data suggest that Selective serotonin reuptake inhibitors (SSRIs) may improve motor recovery after stroke, the results from clinical studies are conflicting. AREAS COVERED Six international electronic databases (Cochrane, PubMed, Embase, Web of Science, CINAHL, and PsycINFO) and four Chinese electronic databases (CBM, CNKI, WanFang Data, and VIP) were systematically searched up to April 2021. Co-primary outcomes were motor function and tolerability. Secondary outcomes included disability, neurological function, continuous depression scores, and adverse events. RESULTS 25 randomized controlled trials including 4777 participants were identified. Pooled analyses found SSRIs significantly improved motor function [standardized mean differences (SMD), 0.72; 95% CI, 0.46 to 0.99], disability (SMD, 0.79; 95% CI, 0.51 to 1.06), neurological function (SMD, -0.58; 95% CI, -0.77 to -0.39) and continuous depression scores (SMD, -0.36; 95% CI, -0.70 to -0.02). SSRIs were associated with increased seizure (risk ratio, 9.00; 95% CI, 1.69 to 47.91) and gastrointestinal side effects (risk ratio, 2.26; 95% CI, 1.56 to 3.28), but similar risk of all-cause discontinuations when compared with the control group (risk ratio, 1.11; 95% CI, 0.79 to 1.56). EXPERT OPINION SSRIs are effective and well-tolerated to promote motor recovery after stroke, but may increase the risk of seizures and gastrointestinal adverse effects.

Fiber-reinforced polymer (FRP) bars are one of the promising alternatives for steel bars used in concrete structures under corrosion or non-magnetic environments due to the unique physical properties of FRP materials. When compared with steel bars, FRP bars are difficult to be spliced in field application due to their anisotropy and low shear and compressive strengths. In view of this, the paper presents a new non-metallic connection system (i.e., resin-filled glass fiber-reinforced polymer (GFRP) pipe connection system) for the butt splicing of FRP bars. With the proposed connection system and a simplified trilinear interfacial bond-slip model, a set of design formulas were derived based on the requirement that the proposed connection system should provide a load transfer capacity beyond the tensile capacity of the spliced FRP bars (i.e., to fulfill the high tensile strength of FRP materials). Besides, considering the fabrication error-induced load transfer capacity reduction of the connection system in field application, a correction factor was introduced in the paper to compensate for the reduced load transfer capacity by increasing the FRP bar anchorage length. At last, to estimate the effectiveness of the proposed connection system and the derived design formulas, nine specimens were fabricated with a kind of commercially available basalt fiber-reinforced polymer (BFRP) bars and the designed connection system and tested under unidirectional tension to study their tensile performance. With the comparison between the tested and theoretical results, the effectiveness of the proposed connection system and the derived design formulas are verified.

Environmental temperature serves a major driver for adaptive changes in wild organisms, however, its role in domestication has been less characterized. To uncover the mechanisms of cold tolerance in domestic animals, we sequenced genomes of 28 cattle at median coverage from warm and cold areas across China. By characterizing the population structure and demographic history, we identified two genetic clusters, i.e., northern and southern cattle groups, and a common historic population peak at 30 kilo years ago. Genome scan of cold tolerant breeds revealed genes that under selection sweeps enriched in thermogenesis related pathways. Specifically, we determined a substitution of PRDM16 (p.P779L) in north cattle, which maintains the formation of brown adipocytes through boosting expression of thermogenic related genes, indicating a vital role of this gene in cold tolerance. The findings provide a basis of genetic variations in domestic cattle that shaped by temperature environments and highlight a role of reverse mutation in livestock species.

Background& AimsThe Coronavirus Disease 2019 (COVID-19) has become a global epidemic and has caused a lasting and huge loss of life security, economic development and social stability in more than 180 countries around the world. Unfortunately, there is still no specific treatment for COVID-19 till now, therefore, at this point, all potential therapies need to be critically considered. LL-37 is one of the best-studied human antimicrobial peptide (AMPs) that has a broad-spectrum activity against bacteria and viruses. The use of living, genetically modified organisms (GMOs) is an effective approach for delivery of therapeutic proteins. The aim of this study was to determine the safety and efficacy of the Lactococcus lactis which has been genetically modified to produce the therapeutic human antimicrobial peptide LL-37 (herein after referred to cas001) in the patients of COVID-19.MethodsFirstly we constructed genetically modified food-grade probiotic, Lactococcus lactis, with sequence of seven tandem repeats of mature human LL-37 under control of the nisin-inducible nisA promoter to produce the cas001. A total of 20 healthy SD rats, half male and half female (There were five male and five female in the control group, the same in treatment group) were used to observe the acute toxic reaction and death after daily administration of cas001 for three weeks, which helps to provide necessary reference basis for clinical dose selection, verificaition of toxic reaction and possible target organs. According to the estimated clinical dosage of 1 × 108CFU /kg/day, considering the conversion of body surface area, the dose for rats should be multiplied by 6.17 to 6 × 108 CFU/kg/day. We administrated 100 times higher dose at 6 × 1010 CFU/ /kg/day to rats. In order to investigate the pharmacokinetics of cas001, male SD rats (body weight 250-300g, 1 × 1010 /animal, n=3) were given oral administration of LL-37 bacteria powder. The concentration of LL-37 in the blood before and after gavage was detected by ELISA kit (Hycult biotechnology Cat# HK321).Human clinical study was approved by Ethics committee of Chinese PLA General Hospital (S2020-074-04) and a total of 11 patients with mild symptoms were enrolled in Wuhan hankou hospital and Huoshenshan hospital. They were enrolled voluntarily and all patients signed informed consent. Among them, there were 5 males and 6 females, aged 55 ± 12 (36-70) years old, and the duration from onset to medication enrollment was 35 ± 19 (5-68) days. 6 patients were nucleic acid positive and 5 patients were nucleic acid negative when they were enrolled. All patients received the oral drug cas001 treatment according to requirement(1 × 109 CFU/capsule, 3 capsules/time, three times a day for 3weeks), with an average follow-up time of 33 ± 15 days (see table 1 for the results).FindingsWestern blot analysis shows that reasonable amount of LL-37 were induced by different concentrations of nisin, which means we have successfully constructed cas001. In the pre-clinical safety evaluation test, after three weeks administration of cas001, no adverse effects were observed on the rat’s body weight, food and water intake, hematological or serum biochemical parameters. The results showed that the LD50 of cas001 was higher than that of the 100 times of the expected clinical dose of 6 × 1010 CFU/day. These results showed that cas001 could be safe in animal experiments. In addition, rat pharmacokinetics results showed that the serum concentration of LL-37 reached peak 2 hours after gavage of cas001 and returned to basal level 6 hours after gavage. During study period, the volunteers did not feel any discomfort while taking the cas001 capsules, and two hours after oral administration, the concentration of LL-37 were increased in healthy volunteers.cas001 shows definite effect in the improvement of gastrointestinal symptoms and is possible to have effects in improving the systemic symptoms and respiratory symptoms and may play a role in the improvement of results of nucleic acid test and lung CT test. 11 patients enrolled showed good compliance, tolerance, subjective feeling and actively interacted with the doctors. None of the patients had any adverse reactions.ConclusionsBased on above observations, we conclude here that as an oral anti-viral agent, cas001 displayed good safety profiles. It is very hard to reach conclusion of clinical outcomes related to the cas001, although changes of several symptoms indicate encouraging findings.

We theoretically propose a dual-channel bistable switch based on a monolayer Z-shaped graphene nanoribbon nanoresonator (NR) coupled to a metal nanoparticle (MNP). We show that the bistable nonlinear absorption response can be realized due to a competition and combination of the exciton-plasmon and exciton-phonon interactions. We map out two-dimensional and three-dimensional bistability phase diagrams, which reveal clearly the dynamical evolution of the roles played by these two interactions in managing optical bistability (OB) at all stages. Specifically, the bistable switch proposed can be controlled via a single channel or dual channels by only adjusting the intensity or frequency of the pump field. In/outside these channels, the switch will be turned on/off. The results obtained here not only can be employed to measure precisely the distance between the MNP and the NR but also provide promising applications in optical switching and optical storage.

The advance of microscopic imaging technology has enabled the observation of primate brain in its entirety and at single-neuron resolution. It is then an urgent need to develop means for automated analyses of these brain images, e.g. neuron segmentation. Deep learning is demonstrated an appealing approach for segmentation of natural images, but the success of deep learning is highly dependent on the large-scale and well-built training data that are costly to collect. In this paper, we take a step towards the goal of neuron segmentation from primate brain images, using a weakly supervised approach. We build – to our best knowledge – the first dual-channel three-dimensional image dataset of macaque brain for neuron segmentation. We propose two kinds of “weak” labels, i.e. central points and rough masks, to prepare training data with an affordable cost. Accordingly, we design a weakly supervised learning method for neuron instance segmentation where instances can be easily extracted from the predicted peak-shape probability maps. Experimental results have shown the effectiveness of our approach. We also verify the efficiency of the proposed method on a public nuclei dataset. Our dataset and code have been published at https://braindata.bitahub.com/.

Due to high vacuum environment of spacecraft orbiting and complex external surface structure of spacecraft cabin, outboard leak detection of spacecraft in-orbit cannot directly adopt existing mature technology. In this article, outboard gas status of spacecraft leakage in-orbit is simulated through computational mechanics and Monte Carlo simulation methods. The simulation results show that complex external surface structure of spacecraft cabin, especially external thermal control layers composed of multilayer insulation material, obviously blocks leakage gas into astrospace and reduces detection sensitivity of outboard leak detection methods. This simulation process and results can provide analyze method and theoretical data for detection scheme design and testing instrument selection of outboard leak detection in the future.

Systemic treatment is necessary for one third of patients with renal cell carcinoma. No valid biomarker is currently available to tailor personalized therapy. In this study we established a representative panel of patient derived xenograft (PDX) mouse models from patients with renal cell carcinomas and determined serum levels of high mobility group B1 (HMGB1) protein under treatment with sunitinib, pazopanib, sorafenib, axitinib, temsirolimus and bevacizumab. Serum HMGB1 levels were significantly higher in a subset of the PDX collection, which exhibited slower tumor growth during subsequent passages than tumors with low HMGB1 serum levels. Pre-treatment PDX serum HMGB1 levels also correlated with response to systemic treatment: PDX models with high HMGB1 levels predicted response to bevacizumab. Taken together, we provide for the first time evidence that the damage associated molecular pattern biomarker HMGB1 can predict response to systemic treatment with bevacizumab. Our data support the future evaluation of HMGB1 as a predictive biomarker for bevacizumab sensitivity in patients with renal cell carcinoma.

We designed and numerically investigated a mechanism to enhance the polarization rotation when THz radiation passes through an array of multilayered graphene/insulator disks placed in a static magnetic field. The observed giant Faraday rotation is due to plasmonic coupling in the disks leading to the enhanced dipole oscillation strength of plasmonic antibonding states. With additional electromagnetic coupling between the disks in the array, the Faraday rotation angles nearly 30° are achieved in a relatively small external magnetic field of around 1 T. The operation wavelength can be tuned within the THz spectral range by controlling the Fermi level of graphene, number of graphene layers, and disk size and period. The proposed mechanism opens up a way to design the ultrathin magneto-optical nanophotonic devices and polarization rotators with high transmittance in the mid-infrared range.

A miniaturized linear ion trap mass spectrometer with continuous atmospheric pressure interface has been built in our lab. Significant extension in mass range and reduction in power consumption have been realized by the supplemental alternating current frequency scan mode. However, relatively poor sensitivity has been witnessed, which is directly dominated by the detection efficiency of the ion detector. Theoretical analysis has been implemented to find ways to improve the detection efficiency. The results show that enhanced sensitivity can be obtained by applying a direct current voltage on the pair of electrodes in eject direction. Experiments show that the sensitivity has been improved by more than one time due to the application of direct current voltage. With this design, this homemade miniature linear ion trap mass spectrometer can be used to analyze more rarefied samples, especially to on-site chemical analysis and space application.

In this paper, we demonstrate the effect of polarization conversion in a plasmonic metasurface structure, in which each unit cell consists of a metal bar and four metal split-ring resonators (SRRs). Such effect is attributed to the fact that the dark plasmon mode of SRRs (bar), which radiates cross-polarized component, is induced by the bright plasmon mode of bar (SRRs) due to the electromagnetic near-field coupling between bar and SRRs. We find that there are two ways to achieve a large cross-polarized component in our proposed metasurface structure. The first way is realized when the dark plasmon mode of bar (SRRs) is in resonance, while at this time the bright plasmon mode of SRRs (bar) is not at resonant state. The second way is realized when the bright plasmon mode of SRRs (bar) is resonantly excited, while the dark plasmon mode of bar (SRRs) is at nonresonant state. It is also found that the linearly polarized light can be rotated by 56.5 0 after propagation through the metasurface structure. Furthermore, our proposed metasurface structure exhibits an asymmetric transmission for circularly polarized light. Our findings take a further step in developing integrated metasurface-based photonics devices for polarization manipulation and modulation.

In this paper, we propose a method to construct geometric-phase-based spin Hall metalens, which consists of identical metal nanoholes with spatially variant orientations. It is demonstrated that the metalens can realize simultaneous focusing for different spin states in the broad spectral range of 550–900 nm due to the extremely similar hyperbolic phase profiles at different optimized values of wavelength and focal length. The transverse and longitudinal positions of spin-dependent focal spots can be arbitrarily manipulated by adjusting the orientation angles of metal nanoholes. The intensities of the spin-dependent focal spots can be effectively controlled by the proportion of the phase profile associated with right- or left-hand circularly polarized component. In addition, our designed metalens enables the focusing beyond the optical diffraction limit across the above wavelength coverage as the phase profile only contains right or left-hand circularly polarized component. It is expected that our simple and novel metalens would be applied in polarimetric imaging, optical sensing, and photon spin splitting.

With the rapid development of space technology in China, it is urgent to use mass spectrometer to detect the space environment. In this work, a space miniature magnetic sector mass spectrometer is evaluated, which consists of three subsystems: (1) physical unit, (2) electric control unit, (3) and high voltage power. It has 90° magnetic sector-field analyzer with double trajectory, in which a trajectory measurement range is from 1 to 12 amu, the other range is from 6 to 90 amu.The mass spectrometer has two work models, one is used to measure space neutral gas when the filament of mass spectrometer ion source turned on, the other is used to measure space charged ions when the filament turned off. The absolute resolution of this device is less than 1 amu, the minimum detectable ion current is about 10−13 A, and the sensitivity is 10−6 A/Pa (N2). Its overall size is 170 mm × 165 mm × 170 mm, its weight is 4.5 kg, and its power consumption is 18 W. A series of environmental adaptability tests, including high and low temperature cycle, shock, vibration, thermal vacuum cycle, were carried out on the ground before launching, and sensitivity and peak position were also calibrated on the ground. In November 2012, the mass spectrometer was carried by an experimental satellite to 499 km sun synchronization and is still working right now. It successfully detected the atmosphere compositions both in the satellite orbit and gas-emitted from satellite, including O, He, 12CO2, 13CO2, H2, N2, O2, H2O, and so on.

We report the tunable enhanced transmission of light through a hybrid metal–graphene structure, in which a graphene ribbon array is situated over a metallic grating. The graphene ribbon is employed to make the graphene–insulator–metal waveguide of finite length as a Fabry–Perot (F–P) cavity. When the slit of metallic grating is opened at the position with a maximal magnetic field in F–P resonant cavity, the transmission of light through metallic grating is greatly enhanced since the strongly localized magnetic field is effectively coupled to the slit. The transmission spectrum and the enhancement factor can be adjusted by changing geometrical parameters including the width and the length of slit, the width of graphene ribbon and the period of metallic grating. The transmission peaks exhibit a broad tuning range with a small change in the Fermi energy level of graphene. Moreover, the enhancement factor of transmission peak can be manipulated by the Fermi energy level and the carrier mobility of graphene, and an enhancement factor of 154 is obtained. The findings expand our understanding of hybrid metal–graphene plasmons and have potential applications in building active plasmonic devices.

Sugarcane streak mosaic virus (SCSMV) is one of the pathogens causing sugarcane mosaic disease (SMD). Transcriptome of a susceptible sugarcane cultivar challenged by SCSMV was studied by high-throughput, paired-end RNA sequencing. Overall, we obtained 63,025 unigenes, including 14,384 unigenes measuring more than 1 kb each. We annotated 38,505 unigenes with COG, GO, KEGG, KOG, Pfam, Swiss-Prot and Nr. We screened 4982 differently expressed genes (DEGs) including 3841 annotated DEGs, of which 3791 were up-regulated, and 50 were down-regulated. The expression of DEGs in the three KEGG pathways, unbiquitin proteolytic system, proteasome and translational pathways in endoplasmic reticulum (ER) was investigated in response to stress and unfolded protein response (UPR). Interestingly, the DEGs in the 3 pathways were up-regulated. We tested eight DEGs encoding proteins in response to ER stress and UPR. We found that these genes were up-regulated in sugarcane challenged by SCSMV. This study presented the first report of the sugarcane transcriptome following SCSMV infection. It sheds light on the genetic mechanisms in sugarcane in response to SCSMV infection.

Background Infertility has become a global health issue with the number of couples seeking in vitro fertilization (IVF) worldwide continuing to rise. Some couples remain childless after several IVF cycles. Women undergoing IVF face greater risks and financial burden. A prediction model to predict the live birth chance prior to the first IVF treatment is needed in clinical practice for patients counselling and shaping expectations. Methods Clinical data of 7188 women who underwent their first IVF treatment at the Reproductive Medical Center of Shengjing Hospital of China Medical University during 2014–2018 were retrospectively collected. Machine-learning based models were developed on 70% of the dataset using pre-treatment variables, and prediction performances were evaluated on the remaining 30% using receiver operating characteristic (ROC) analysis and calibration plot. Nested cross-validation was used to make an unbiased estimate of the generalization performance of the machine learning algorithms. Results The XGBoost model achieved an area under the ROC curve of 0.73 on the validation dataset and showed the best calibration compared with other machine learning algorithms. Nested cross-validation resulted in an average accuracy score of 0.70 ± 0.003 for the XGBoost model. Conclusions A prediction model based on XGBoost was developed using age, AMH, BMI, duration of infertility, previous live birth, previous miscarriage, previous abortion and type of infertility as predictors. This study might be a promising step to provide personalized estimates of the cumulative live birth chance of the first complete IVF cycle before treatment.

Collaborative geospatial data editing is different from other collaborative editing systems, such as textual editing, owing to its geospatial nature. This paper presents a version-based lightweight collaborative geospatial editing method for urban planning. This method extracts editing data and generates a version for collaborative editing, which reduces the data size and thus allows for a high feedback speed. A replication mechanism is engaged to replicate a version for the client to freely edit, which ensures constraint-free editing in collaboration. Based on this method, realizing the fact that heterogeneous geospatial data and non-professional users are involved, a lightweight architecture, integrating web services, and component technologies, was proposed. This architecture provides a unified data access interface and powerful editing ability and ensures a high feedback speed and constraint-free editing. The result of the application of the proposed approach in a practical project demonstrates the usability of collaborative geospatial editing in urban planning. While this approach has been designed for urban planning, it can be modified for use in other domains.

Volumetric instance segmentation plays a significant role in biomedical morphological analyses. The improvement of segmentation accuracy has been accelerated by the progress of deep learning-based methods. However, such methods usually rely heavily on plenty of precise annotation, which is time-consuming and may need some expert knowledge to label manually. Although there are several studies focusing on weakly supervised methods in order to save the labeling cost, previous approaches still more or less require voxel-wise annotation. In this paper, we propose a weakly supervised instance segmentation method that needs no voxel-wise labeling. Our approach takes advantage of two advanced techniques: one is the popular proposal-based framework (Faster R-CNN in this paper) for instance detection, and the other is the peak response mapping (PRM) for finding visual cues of instances. Then a new thresholding method combines detected boxes and visual cues to generate final instance segmentation results. We conduct experiments on two biomedical datasets, one of which is a large-scale mouse brain dataset at single-neuron resolution collected by ourselves. Results on both datasets validate the effectiveness of our proposed method.

Neuron segmentation is an important task for automatic analyses of brain images that are of huge volume. Previous methods for neuron segmentation rely on handcrafted image features, and have difficulty in coping with high-resolution, low signal-to-noise-ratio brain images. Convolutional neural network (CNN) has achieved remarkable success in natural image segmentation, but CNN requires accurately labeled data for training that are difficult to achieve on brain images of huge volume. In this paper, we present a weakly supervised learning strategy to deal with the inaccurate training data problem, and thus adopt 3D CNN to perform automatic soma segmentation from brain images. We test our method on our own collected mouse brain images that are of single-neuron resolution, and results show that 3D CNN-based method outperforms the traditional methods by a significant margin.

The non-linear responses of optical materials offer useful mechanisms for optical switching, novel optical sources, and harmonic frequency conversion. However, the non-linear response of traditional materials is usually extremely weak and requires high input power for excitation. In this study, we theoretically propose a scheme for enhancing the third harmonic generation (THG) efficiency and output power of layered graphene disks array by introducing a plasmonic antibonding state with enhanced oscillation strength due to plasmonic coupling. We verify that, the THG efficiency of a double-layer stacked graphene/SiO2 disk structure under relatively low input intensity can be significantly enhanced more than one order of magnitude with appropriate design, as compared with monolayer patterned graphene nanostructure. We also demonstrate that the THG efficiency can be further improved by optimizing the geometry parameters such as spacer distance and Fermi energy. Our results offer an effective mechanism for significantly improving THG efficiency in the mid-infrared and terahertz ranges, thereby paving the way for new frequency converters and modulators in optical communication and signal processing.

Objective:To evaluate the safety, efficacy, and feasibility of rituximab, fotemustine, pemetrexed and dexamethasone (R-FPD) regimen for primary central nervous system lymphoma (PCNSL) patients. Methods:A prospective, single-center, single-arm, phase II clinical trial. Patients with newly diagnosed PCNSL diagnosed from the First Affiliated Hospital of Zhengzhou University from July 2018 to July 2020. R-FPD regimen consisted of rituximab (375 mg/m2 i.v. on D0), fotemustine (100mg/m2 i.v. on D1) ,pemetrexed (600mg/m2 i.v. on D1), and dexamethasone (40 mg i.v. on D1).(NCT04083066) Results: 30 patients were included. After two cycles, the objective response rate(ORR) was 96.4%(27/28,26 PR,1 CR,0 SD,0 PD,2 Censored),the disease control rate(DCR) was 96.4%(27/28); After four cycles, the ORR was 71.4% (15/21, 5PR,10 CR,1SD,5PD,7NR,2 Censored),DCR was 76.2%(16/21). The median progression-free survival (PFS) was 20.3 months (95%CI:5.2--35.4),The median overall survival (OS) was 22.0 months (95%CI:16.1-27.9).The grade III-IV toxicities were mainly leukopenia(17.9%), thrombocypenia(25%) and anemia(10.7%). Conclusion: Fotemustine-based in combination with Rituximab chemotherapy can improve outcomes with the progress free survival and the overall survival benefits, as well as with better tolerability for newly diagnosed PCNSL patients. Keywords: rituximab; primary central nervous system lymphoma; pemetrexed; fotemustine; efficacy Disclosures No relevant conflicts of interest to declare.

Based on the interplay between propagating surface plasmon polaritons (PSPs) in graphene ribbon and double layer sheets structure, we theoretically demonstrate a tunable strong coupling mechanism significantly different from reported conventional noble metal nanostructures. The strong electromagnetic coupling between the low order antisymmetric and high order symmetric PSPs modes occurs due to the intersections of dispersion curves, which leads to a modification of plasmonic dispersion and multiple significant anti-crossing regions. Of particular, this strong coupling is controllable through external gate voltage of graphene sheets or ribbon. The results offer an effective regime to dynamically tune the interaction of graphene PSPs, which may find applications in the field of nanophotonic devices in the mid-infrared range.

This paper presents an investigation of carbon nanotube (CNT) emitter-based ionization gauge. The metrological performances of this CNT emitter-based ionization gauge were investigated and studied by numerical and experimental methods. The electron source was constructed with multi-wall nanotubes (MWNT), which were grown on stainless steel substrate using thermal chemical vapor deposition (CVD) technique. The influence of anode and reflector voltages on the anode current Ia and ion current I+ were studied in this work, respectively. The electron transmittance increases significantly along with the increase of anode voltage, and I+ increases dramatically as the increase of reflector voltage from 0 V to 525 V, but it decreases again with the further increase of reflector voltage to 600 V. The studied gauge with CNT cathode has good measurement linearity from 1.0 × 10−8 Pa to 5.0 × 10−4 Pa and a gauge sensitivity of 0.03 Pa−1 for argon is achieved.

We present a computational study of the plasmon resonances in a periodic square coaxial hole array in a graphene sheet, which consists of a square hole array and a square strip array. According to charge oscillation picture, we find that a new plasmon mode, which locates on the edges of square hole along the polarization direction of incident light, emerges in our proposed structure. Two hybridized plasmon resonance modes (i.e., symmetric and asymmetric plasmon resonance modes) are formed due to two different manners of coupling between the new plasmon mode of square hole and the plasmon mode of square strip. The two plasmon resonance modes can be tuned over a wide wavelength range by a small change in the chemical potential of graphene. Furthermore, the two plasmon resonances can also be controlled by changing L x and L y (which are the strip offsets from the hole center perpendicular and parallel to the polarization direction of incident light, respectively), originating from the change in the strength of electromagnetic coupling between square hole and square strip. Our study gives an insight into the physical mechanism of plasmon resonances in square graphene coaxial hole array, and our findings will be useful for designing graphene-based plasmonic devices and metamaterials.

In this paper, we propose a high performance biosensor which allows the coupling between surface plasmon polariton (SPP) mode in metal–insulator–metal waveguide and planar waveguide (PWG) mode. The reflection curve exhibits a sharp dip originated from PWG mode when there is a weak coupling between SPP and PWG modes. The strong coupling between SPP and PWG modes results in asymmetric Fano resonance and plasmon-induced transparency. The sensitivities of PWG mode dip and Fano resonance achieve 9733 and 7050 RIU−1, respectively, which are enhanced by 2 ∼ 3 orders of magnitude compared to those of conventional surface plasmon resonance sensors.

Relation extraction becomes one important task in information extraction and it is becoming more and more used to discover relations from text. However, it is difficult to combine context information for relation extraction and some important information may appear many times in one sentence. In order to solve these problems, this paper presents Gated Recurrent Unit Networks with attention (CHGRU) model to catch important information in a sentence. In this model, we use the gated unit networks for embedding sentence semantics. Then, we build word-level attention to capture informative sentences with accurate relation patterns. On real-world datasets, our experimental results gains great improvements about relation extraction as compared with others.

This study aimed to analyze the clinical characteristics and prognostic factors of patients, divided into over 40-year-old group or not, with precursor T-cell lymphoblastic lymphoma (Pre-T-LBL). Based on the retrospective analysis of the clinical data of 59 patients with Pre-T-LBL during the period from December 2010 to December 2015, albumin level, anemia, pleural or pericardial effusion, protocol, therapy response, mediastinal mass, lactate dehydrogenase (LDH), and international prognostic index (IPI) or age-adjusted international prognostic index (aaIPI) were summarized. For patients aged

A miniaturized ion trap mass spectrometer with continuous atmospheric pressure interface was built, which could be used in conjunction with internal ionization (in-vacuum plasma ionization) and external ionization (electrospray ionization). To improve its mass range, a supplemental AC signal frequency scan mode was performed for this miniature mass spectrometer, in which the fundamental RF signal was remained constant with an amplitude as low as several hundreds volts. Experiments showed that the upper limit of the mass range can be extended to 2500 Da for the miniature mass spectrometer developed in this work, and the power consumption can be reduced by 2/5, while maintaining good balance with performance parameters such as stability, sensitivity, and resolution. Due to the improvement in mass range and significant reduction in energy consumption compared with the instrument using the traditional resonant ejection mode, the scan method developed in this work is helpful to promote the miniature design of mass spectrometers for field analysis and space exploration.

Because of large amounts of unstructured data generated on the Internet, entity relation extraction is believed to have high commercial value. Entity relation extraction is a case of information extraction and it is based on entity recognition. This paper firstly gives a brief overview of relation extraction. On the basis of reviewing the history of relation extraction, the research status of relation extraction is analyzed. Then the paper divides theses research into three categories: supervised machine learning methods, semi-supervised machine learning methods and unsupervised machine learning method, and toward to the deep learning direction.

We perform a theoretical study of the bistable four-wave mixing (FWM) response in a coupled system comprised of a semiconductor quantum dot (SQD) and a photonic crystal (PC) nanocavity in which the SQD is embedded. It is shown that the shape of the FWM spectrum can switch among single-peaked, double-peaked, triple-peaked, and four-peaked arising from the vacuum Rabi splitting and the exciton-nanocavity coupling. Especially, we map out bistability phase diagrams within a parameter subspace of the system, and find that it is easy to turn on or off the bistable FWM response by only adjusting the excitation frequency or the pumping intensity. Our results offer a feasible means for measuring the SQD-PC nanocavity coupling strength and open a new avenue to design optical switches and memories.

We theoretically propose a scheme of a tunable bistable device based on a coupled semiconductor quantum dot–metal nanoparticle nanosystem in the simultaneous presence of a strong pump laser and a weak probe laser with different frequencies. The results show that it is easy to turn on or off the optical bistable effect in such system by switching the polarization direction of the pump field, and the bistability thresholds are highly sensitive to the intensity, frequency, polarization direction of the pump field, and the interparticle distance. In addition, the nonlinear absorption in the two stable states exhibits a ratio as high as 104 arising from the three-photon effect, which implies that our nanosystem can also be used as an optical memory cell.